This invention relates to a single-control mixing valve in which the sealing seat, instead of being provided directly in the body of the valve, is arranged on an auxiliary member.
In the single-control mixing valves, in which the delivered rate and the mixing ratios of hot and cold water are controlled by a plug which is rotatable and axially movable in the body of the valve, there arises the problem of the considerable resistance opposed by the friction to the movement of the plug, which resistance restrains the control and must therefore be reduced as far as possible. To this end, it is suitable that the plug itself have a reduced diameter, but on the other hand this provision generates serious problems in machining the inner cavity of the body of the valve, especially when said cavity has undercuts formed therein, because the automatic machines do not allow one to suitably use long and thin cantilevered tools. Especially when the sealing seat of the valve is intended to be closed by a gasket which approaches the seat from the inside of the valve towards the outside, the exact machining of said seat, which must be rounded and free from any imperfection, is very difficult. Moreover, repairs of the seat in case of deterioration thereof are absolutely impossible.